Historical perspective of artisanal encircling gillnet use at the Brazilian coast: Changes in fishing behaviour is mirrored by dwindling stocks

Abstract

AbstractManaging coastal resources sometimes requires looking into the past, as this provides a baseline against which present conditions may be gauged. The present study evaluated the circumstances that led Brazilian coastal fishers to modify their use of encircling gillnets. Other stressors (i.e. water pollution and habitat degradation) acted synergistically on the fisheries dynamic between 1950 and 2016. Declining catches of several species were observed through fishers' historical perception and through fisheries landing records. Three notable trends in net handling were associated with distinct historical periods. Specifically, pressures from modern fishery practices and gear (e.g. monofilament nets), the adoption of spiral setting arrangements and the increasing use of trammel nets appear responsible for the decline of many stocks. Mullet, seabass, jack and pilchard stocks decreased over time and were associated the changes witnessed in the encircling net operations. These changes occurred in response to overexploitation of fish stocks, to exploit the dwindling fisheries resources. The study also discusses the reasons leading fishers to accept how encircling gillnets ought to be used, their interpretation of such changes and the implications these changes have for fisheries management.